BIODIGESTORES

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BIODIGESTORES
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Materials

• 1 PVC macho adaptor ½
• 2 five gallon buckets with the bottoms removed
• 1 PVC hembra adaptor ½
• 2 non-corrosive washers (4-6 inch diameter) with
  a ½ hole
• 2 rubber spacers 1 inch of equal or greater
  diameter than the
• washer
• 6. 1 PVC Tee conjunction ½
• 7. 1 PVC ninety degree conjunction ½
• 8. 1 ½ metal valve
• 9. 4x4 inch piece of metallic screen
• 10. 3-4 feet of ½ PVC tubing
• 11. 1 roll of plastic hose ½ (amount determined
  by distance of the
• biodigestor from the kitchen)
• 1 two liter plastic bottle
• 4 one meter sturdy stakes
• 14. 2 two meter posts
• 15. ¼ gallon PVC glue
• 16. Rope 5-10 feet longer than the biodigestor
  bag
• 17. Saw (to cut PVC), scissors, machete, pick
  axe, shovel, hoe, twine or string

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• SIGHT PREPERATION
• A ditch 8m x 1m x 60cm with an approximate
• difference of 5cm from entrance to exit
• (ditch dimensions will vary according to plastic)

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Clear ditch of any debris that could puncture the
plastic.
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Walls of ditch spackled with mud to cover
protruding root ends.
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2. Excavate a stair at both ends of the ditch
(approximately 20cm deep, 45cm wide).
(
1. Provisional, well secured posts need to also
be installed at both ends of the ditch (approx.
2ft. behind the stairs).
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Extend 10m of plastic over a clean concrete
surface (note no shoes on the plastic).
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After cutting the first 10m, extend an equal
amount of plastic again through the cut portion.
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After extending the second portion, take care to
align the two bags so as to avoid any folds or
bunching.
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Once the two bags are aligned, extend a rope
(approximately 15m) through the double bag and
tie it off at the secured posts on both ends of
the ditch so as to leave the bag hanging,
however, touching the ground.
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Once the bag is in place the gas outlet can be
installed. Youll need two non-corrosive palm
size washers, and two rubber spacers of equal or
greater size.
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Insert a ½ inch PVC hembra adaptor with the
rubber spacer on top of the non-corrosive washer,
and likewise with the ½ inch PVC macho adaptor.
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The location of the gas outlet will depend
largely on the general surroundings of the ditch.
The hole does not need to be in the middle of
the bag, it can be placed towards one end or
another so as to take advantage of hanging
branches for the outlets support. If there are
no surrounding branches to support the outlet
tubing, a post may be installed to serve the same
purpose.
Once the location has been chosen, make a small
cut, no bigger than a ½ inch, through the double
bag.
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The hembra adaptor is placed inside the bag,
tightened with the macho adaptor on the outside.
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Once the gas outlet is in position, the bag is
filled with unchlorinated water to approximately
4 inches below the stairs on both ends of the
ditch.
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As the bag fills with water, the rope sustaining
it is removed and the outlet tubing is glued into
place, taking into consideration the direction of
the kitchen and the height of any supporting
branches.
Note take special care that no glue touches the
bag.
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After cutting a ½ inch size hole in a 2 liter
bottle, a tee conjunction is placed at a distance
determined by the supporting branch. The 2 liter
is then filled approximately half full with water
to submerge the PVC extension. The submersion
allows for excess gas to escape while preventing
air from entering the system.
A small metal screen is inserted into the tee
conjunction to prevent the flame from passing
into the system.
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Once tied to the supporting branch, the primary
valve is installed at a short distance from the
excess gas release.
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Two stakes are hammered securely in place at a
distance the width of the bucket on both ends of
the ditch. The plastic is then pulled through
the bucket, folded over, and tied to both bucket
and the stakes with a long 2 inch wide strip of
rubber (any rope will do).
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It is essential that each bucket be submerged in
at least 3-4 inches of water to prevent gas from
escaping. The entrance bucket rest in an
up-right position while the exit bucket is tilted
at a 45 degree angle to allow the passage of
excess liquids.
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The suggested initial input to bring the
biodigestor up to a functional level is 20
buckets of two shovels of cow manure (one shovel
of pig manure) mixed with five gallons of water.
The same mixture is added once a day for at least
eight consecutive days following the original
mixture after which point the input may continue
as such or decrease to every other day. One can
expect a period of at least 30-60 days until the
biodigestor is operating at full capacity.
Note all mixtures should be well liquefied, any
incorporated fruit should also be well shredded.
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In the Kitchen
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Two valves are secured to the stove, then
depending upon the placement of the stove and the
direction of the incoming tubing, a 90 degree and
tee conjunction are placed accordingly.
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A small piece of PVC is measured and cut to
bridge the two conjunctions.
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To avoid reaching across an open flame to close
the valves, recommended valve placement is
between the burner and the stove operator.
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Buen Provecho!